The present invention relates to a wind power generation apparatus, a wind power generation system and a power system control apparatus for supplying to a power system necessary reactive power for the power system.
Normally, a wind power generation apparatus converts wind energy into rotational energy and generates rotational torque at a rotor of a generator. The apparatus produces electric power from induced torque, and outputs it to a power system, thereby converting the wind energy into active power and supplying the active power to user home and factories connected to the power system.
In addition to the active power consumed by resistor components, the power system includes reactive power consumed by inductor components and capacity components of power lines and loads. When the inductor components of power lines and loads are large, the voltage drops at the end of the loads of the system, and when the capacity components of loads are large, the voltage rise. Therefore, to maintain an appropriate value of the voltage, it is necessary to regulate the reactive power.
To attain this, the reactive power is normally regulated by adjusting the voltage of a generator of a system, tap-switching the transformer of a substation etc., and using a power capacitor, a branch reactor, a synchronous phase shifter, etc. In addition, since capacitors and inductance devices for various values are required to continuously control the value of reactive power using capacitors and inductance, there can be an apparatus to be used to continuously control the reactive power.
JP-A-2000-333373 and U.S. Patent Application Publication No. 20050046196 describe an apparatus which outputs reactive power to a power system.